水饱和水泥基材料冻结损伤分析

Analysis on Freezing Damage of Saturated Cementitious Materials

浏览量:

关键词:

水泥基材料;抗冻性;裂缝;损伤

Key words:

Cement-based material; Frost resistance; Cracks; Damage

刊期:

2016年第1期

DOI:

文章编号:

1000-4637(2016)01-27-04

基金项目:

作者:

李献忠

单位:

中铁十八局集团第四工程有限公司,天津300350

摘要

摘   要:水饱和水泥基材料冻结时孔隙内产生压力,导致孔壁开裂,是水泥基材料冻融循环劣化的原因之一。根据弹塑性力学和能量守恒原理,定量分析了冻结条件下水饱和水泥基材料内部裂缝的形成及发展,揭示了水泥基材料冻结损伤机理。

Abstract: Pressure creates in saturated pores in cementitious composites when freezing and it leads to the cracking of the pore wall, which is one of the main reasons of the deterioration of cement subjected to freezing and thawing. Based on the plastoelasticity and the principle of conservation of energy, the initiation and propagation of cracks in saturated cement paste under freezing are quantitatively analyzed and the mechanical degradation in mechanical properties of the cement paste is investigated.

结论

根据弹塑性力学和能力守恒原理,建立了水泥基材料水饱和孔隙受冻孔隙压力作用开裂体积计算模型,模型计算得到的开裂体积与既有测试结果一致,表明建立的模型具有可靠性。
利用模型分析不同水灰比的水泥净浆,显示水灰比越大,其相应的裂缝体积分数也越大。水灰比0.4、0.5和0.6的水泥基饱和状态下冻结后开裂体积分数分别为0.042%、0.468%和1.595%。开裂体积分数反映了水泥基材料的损伤程度。

参考文献

[1] Jacobsen S, Gran H C, Sellevold E J, et al. High strength concrete—freeze/thaw testing and cracking[J]. Cement and concrete research, 1995, 25(8): 1775-1780.
[2] Glinicki M A, Litorowicz A. Crack system evaluation in concrete elements at mesoscale[J]. Bulletin of the Polish Academy of Sciences-Technical Sciences, 2006, 54(4): 25-27.
[3] Basista M, Weglewski W. Chemically assisted damage of concrete: a model of expansion under external sulfate attack[J]. International journal of damage mechanics, 2008.
[4] 袁海峰. 水泥基复合材料冻融破坏全过程的微观和宏观定量分析及试验研究[D].南京: 东南大学, 2011.
[5] 材料学. 水泥材料科学导论[M]. 上海: 同济大学出版社, 1991.
[6] Mindess S, Young J F, Darwin D. Concrete[M]. 2003.
[7] Pellenq R J M, Van Damme H. Why does concrete set: The nature of cohesion forces in hardened cement-based materials[J]. Mrs Bulletin, 2004, 29(05): 319-323.
[8] Knott J F. Fundamentals of fracture mechanics[M]. GruppoItalianoFrattura, 1973.
[9] 徐秉业, 刘信声. 应用弹塑性力学[M]. 北京: 清华大学出版社有限公司, 1995.
[10] Diamond S, Dolch W L. Generalized log-normal distribution of pore sizes in hydrated cement paste[J]. Journal of Colloid and Interface Science, 1972, 38(1): 234-244.
[11] Jacobsen S, Marchand J, Boisvert L. Effect of cracking and healing on chloride transport in OPC concrete[J]. Cement and Concrete Research, 1996, 26(6): 869-881.
 

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